Chapter6-ATourofTheCell

What tools do biologists use to study cells?

Biologists use microscopes and biochemistry to study cells.

What are eukaryotic cells characterized by?

Eukaryotic cells have internal membranes that compartmentalize their functions.

Where are the genetic instructions in a eukaryotic cell housed?

The genetic instructions are housed in the nucleus.

How do ribosomes function in a cell?

Ribosomes carry out the genetic instructions by synthesizing proteins.

What is the role of the endomembrane system?

The endomembrane system regulates protein traffic and performs metabolic functions in the cell.

What function do mitochondria and chloroplasts serve?

They change energy from one form to another.

What is the cytoskeleton's role in a cell?

The cytoskeleton is a network of fibers that organizes structures and activities in the cell.

How do extracellular components contribute to cellular activities?

They help coordinate cellular activities.

What was the significance of microscopes in cell biology?

Microscopes allowed scientists to see cells for the first time.

Who was Robert Hooke?

Robert Hooke was the first person to observe and describe cells.

What is the basic unit of life?

The cell is the basic unit of life.

What distinguishes prokaryotic cells from eukaryotic cells?

Prokaryotic cells have no true nucleus or membrane-enclosed organelles.

What term describes the liquid substance inside all cells?

Cytosol is the liquid substance inside all cells.

What are organelles?

Organelles are specialized structures within a cell that perform specific functions.

What is the structure and function of the plasma membrane?

The plasma membrane is a selective barrier that regulates the passage of substances in and out of the cell.

What are ribosomes made of?

Ribosomes are complexes made of ribosomal RNA and proteins.

What is magnification in microscopy?

Magnification is the ratio of an object's image size to its real size.

How does resolution relate to microscopy?

Resolution is a measure of the clarity of the image, indicating the minimum distance two points can be separated and still identified as distinct.

What does contrast refer to in microscopy?

Contrast refers to the differences in light and dark areas of a specimen, making the details stand out.

What is the primary advantage of electron microscopy over light microscopy?

Electron microscopy has a much higher resolution, allowing for the visualization of smaller structures.

What are the two types of electron microscopes?

The two types of electron microscopes are scanning electron microscopes (SEM) and transmission electron microscopes (TEM).

What is cell fractionation?

Cell fractionation is a laboratory technique used to separate cellular components based on size and density.

What are the three main types of fibers in the cytoskeleton?

The three main types are microtubules, microfilaments, and intermediate filaments.

What is the main function of microtubules?

Microtubules provide structural support and facilitate intracellular transport.

How do motor proteins function?

Motor proteins move along microtubules to transport vesicles and organelles within the cell.

What is the central vacuole's role in plant cells?

The central vacuole maintains turgor pressure and stores important substances.

What gives plant cell walls strength?

Cell walls are composed of cellulose fibers that provide structural support.

What is the function of lysosomes?

Lysosomes digest macromolecules and recycle cellular components.

What is the extracellular matrix?

The extracellular matrix (ECM) is a network of proteins and carbohydrates outside the cell that provides structural and biochemical support.

What connects neighboring plant cells?

Plasmodesmata connect neighboring plant cells, allowing for communication and transport.

Describe tight junctions in animal cells.

Tight junctions are connections that prevent leakage of extracellular fluid between epithelial cells.

What role do gap junctions play?

Gap junctions allow for communication and transfer of small molecules between adjacent animal cells.

What is the function of desmosomes?

Desmosomes anchor cells together, providing mechanical strength.

What cellular component is responsible for photosynthesis?

Chloroplasts are the cellular components responsible for photosynthesis.

How do mitochondria generate energy?

Mitochondria generate energy through the process of cellular respiration.

What organelle is known as the powerhouse of the cell?

Mitochondria are known as the powerhouse of the cell.

What is the function of the Golgi apparatus?

The Golgi apparatus modifies, sorts, and packages proteins and lipids for secretion or delivery to other organelles.

What type of cell contains a nucleolus?

Eukaryotic cells contain a nucleolus, which is involved in ribosome production.

What is chromatin?

Chromatin is the complex of DNA and proteins that forms chromosomes within the nucleus.

What is the primary role of ribosomes in cells?

Ribosomes synthesize proteins based on mRNA sequences.

Describe two functions of the rough endoplasmic reticulum (Rough ER).

The Rough ER synthesizes proteins that are secreted or inserted into membranes.

What is the main difference between smooth and rough endoplasmic reticulum?

The Rough ER has ribosomes on its surface, while the Smooth ER does not.

Where is the nucleoid found?

The nucleoid is found in prokaryotic cells and is the region where the cell's DNA is located.

What is a plasmodesmata?

Plasmodesmata are channels between plant cell walls that allow for communication and transport between cells.

What type of cells have chloroplasts?

Chloroplasts are present in plant cells and some algal cells.

What is the structure of a typical ribosome?

A ribosome consists of two subunits made of rRNA and proteins.

What is the role of peroxisomes in a cell?

Peroxisomes contain enzymes that detoxify harmful substances and break down fatty acids.

How do cilia and flagella differ?

Cilia are short and numerous, whereas flagella are longer and typically fewer in number.

What type of junctions allow for communication between animal cells?

Gap junctions allow for communication between adjacent animal cells.

How is the extracellular matrix (ECM) involved in cell signaling?

The ECM can transmit signals between the external environment and the cytoplasm of the cell through integrin receptors.

What process do ribosomes assist in?

Ribosomes assist in protein synthesis.

What organelle is responsible for detoxification of drugs in the liver?

The smooth endoplasmic reticulum is primarily responsible for drug detoxification in the liver.

What is a common feature shared by all cells?

All cells are enclosed by a plasma membrane.

How do cells maintain homeostasis?

Cells maintain homeostasis by regulating the movement of substances across the plasma membrane.

What provides structural support to the cell?

The cytoskeleton provides structural support to the cell.

What is the function of microvilli in intestinal cells?

Microvilli increase the surface area for absorption in intestinal cells.

What are the characteristics of eukaryotic cells?

Eukaryotic cells have a nucleus and membrane-bound organelles.

What is a major component of the plant cell wall?

Cellulose is a major component of the plant cell wall.

Where are ribosomes found in a eukaryotic cell?

Ribosomes can be found free in the cytosol or bound to the rough endoplasmic reticulum.

How do cells use ATP?

Cells use ATP as a source of energy for various biological processes.

What is the role of the nuclear envelope?

The nuclear envelope protects the nucleus and regulates the flow of materials in and out.

What distinguishes rough ER from smooth ER?

Rough ER has ribosomes attached, while smooth ER does not.

How do neighboring plant cells communicate?

Neighboring plant cells communicate through plasmodesmata.

What is the role of integrins in the extracellular matrix?

Integrins connect the ECM to the cytoskeleton and transmit signals between the two.

Which process involves engulfing cellular debris?

Phagocytosis involves engulfing cellular debris.

What is the significance of the Golgi apparatus's polarity?

The polarity ensures correct processing and sorting of substances as they move through it.

What is a unique feature of mitochondria?

Mitochondria contain their own circular DNA and ribosomes.

What is the primary function of chlorophyll within chloroplasts?

Chlorophyll captures light energy for photosynthesis.

What cellular structures help maintain cell shape?

Microtubules and microfilaments help maintain cell shape.

What is the basic unit of classification for all living organisms?

The cell is the basic unit of classification for all living organisms.

What do lysosomes contain that aids in digestion?

Lysosomes contain hydrolytic enzymes that aid in digestion.

What is the evolutionary significance of mitochondria and chloroplasts?

They provide evidence for the endosymbiotic theory.

What are the roles of intermediate filaments in cells?

Intermediate filaments provide tensile strength and help maintain organelle positions.

What are the two primary components of the ECM?

Glycoproteins and proteoglycans are the two primary components of the ECM.

How do cells communicate through the ECM?

Cells communicate through signaling pathways initiated by integrins that connect the ECM to the cytoskeleton.

What is the function of contractile vacuoles in some protists?

Contractile vacuoles help regulate water balance by expelling excess water.

What type of cell junctions serve as anchors between cells?

Desmosomes serve as anchors between cells.

What is a defining characteristic of prokaryotic cells?

Prokaryotic cells lack a true nucleus.

What are food vacuoles responsible for in protists?

Food vacuoles are responsible for digestion in protists.

What happens to chromatin during cell division?

During cell division, chromatin condenses to form visible chromosomes.

What is the relationship between the nucleus and ribosomes?

The nucleus houses the DNA that encodes for ribosomes and proteins, while ribosomes are responsible for protein synthesis.

How do tight junctions contribute to tissue function?

Tight junctions prevent leakage of fluids and help maintain barrier integrity in tissues.

What helps maintain the shape of red blood cells?

The cytoskeleton helps maintain the shape of red blood cells.

What is one role of plant vacuoles?

Plant vacuoles store nutrients and waste products.

What organelle is exclusive to plant cells?

Chloroplasts are exclusive to plant cells.

What is stored in the central vacuole of plant cells?

The central vacuole stores water, nutrients, and waste products.

What cytoplasmic structure allows for cell motility?

Microfilaments allow for cell motility.

How does the extracellular matrix influence cell behavior?

The extracellular matrix interacts with integrins to influence gene expression and cellular function.

What do microtubules and microfilaments contribute to?

They contribute to cell shape, motility, and transport within the cell.

What is the primary role of chloroplasts?

Chloroplasts convert sunlight into chemical energy through photosynthesis.

What can result from malfunctioning lysosomes?

Malfunctioning lysosomes can lead to cell damage and diseases such as Tay-Sachs.

What is the function of the nucleolus?

The nucleolus is involved in the production of ribosomal RNA.

How do cilia and flagella differ in their function and structure?

Cilia are short and numerous, used for movement of fluid over surfaces, while flagella are longer and fewer, used for propulsion.

What do fibroblasts do in connective tissue?

Fibroblasts secrete the components of the extracellular matrix.

What do the terms 'autophagy' and 'phagocytosis' refer to?

Autophagy refers to the degradation of damaged organelles, while phagocytosis refers to the engulfing of particles or cells.

What abundant protein is a major component of the extracellular matrix?

Collagen is a major component of the extracellular matrix.

How are the Golgi apparatus and endoplasmic reticulum connected?

The Golgi apparatus receives products from the endoplasmic reticulum for modification and transport.

What is the function of peroxisomes?

Peroxisomes detoxify harmful metabolites and produce hydrogen peroxide.

What is the primary role of the vacuole in a plant cell?

The primary role of the vacuole is to store nutrients and waste products, and maintain turgor pressure.

What is the relationship between the surface area to volume ratio and cell size?

A high surface area to volume ratio facilitates adequate exchange of materials within a cell.